Method of and machine for grinding or lapping bearing rolls



March 30, 1937. A. B. Ell \llG 2,075,104

METHOD OF AND MACHINE FOR GRINDING OR LAPPING BEARING ROLLS Fiied Feb. e, 1935 2 Sheets-Sheet 1 7 INVENTOR. fl/wkz 5? any BY ATTORNEY);

' Patented Mar. 30, 1937 UNITED STATES PATENT oF-F cE METHOD 'OF AND MACHINE FOR GRINDING R LAPPING BEARING ROLLS Alvin n. Einig, Cleveland Heights, Ohio, assignor to The Motch& Merryweather Machinery Com- pany, Cleveland, Ohio, a corporation of Ohio Application February 6, 1935, Serial No. 5,272

9 Claims. (01. 51-218) This invention relates, as indicated, to methods of and machines for grinding or lapping rolls,

but has reference more particularly to methods of and machines forcontinuously and simulta- 10 the body or peripheral surface of the rolls by.

one operation and the thrust end of the rolls by another operation, these operations being performed in separate or independent machines. In addition to the inaccuraciesfrequently resulting- 16 from the treatment ofthe rolls in separate ma- I 25 forming these operations, and the production of rolls conforming in a high degree with established standards of uniformity and precision.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the 30 means hereinafter fullyv described and particularly pointed out in the claims, the annexed drawings and the following description setting forth in detail certain means and one mode of carrying out the invention, such'disclosed means and mode 35 illustrating, however, but one of various ways in which the principle of the invention may be used.

In said annexed drawings: Fig. 1 is a plan view of a. machine for continuously and simultaneously grinding or lapping the 40 body and thrust end of tapered rolls of the character usually employed in tapered roller bearings, the outline of the grinding or lapping wheel or disk being indicated by dotted lines;

Fig. 2 is a cross-sectional view of the machine, 45 taken on the line 2-2 of Fig. 1; I

Fig. 3 is a plan view of a fragment of the roll carrier;

' Fig. 4 is a view, on an enlarged scale,'of a portion of Fig. 2; 50 Fig. 5 is a view similar to Fig. 4, but showing a roll support or roll race, the spiral track .of which is provided with a crowned bottom;

Fig. 6 is a view similar to Fig. 4, but showing a, roll support with a modified form of track; and

58 Fig. '7 is a view similar to Fig. 4, but showing a support adapted for use in grinding or lapping cylindrical rolls. Referring more particularly to Figs. 1 to 4, inclusive, it will be seen that the machine comprises a circular roll support or race I, a roll 6 carrier 2 and a grinding or lapping wheel orv disk 3.

,The roll support I is stationary andv may be made of'metal, an abrasive composition, bakelite, or other suitable material. It is provided 10 in its upper surface with a spiral track 4,. the track beginning at the extreme left of the supportas viewed in Figs. 1 and 2 and proceeding in a clockwise direction to a point 5, which is spaced a considerable distance from the center of the 16 support. The support I is provided with a central opening 6. A' chute I having an inclined bottom 8 extends from a point adjacent the inner end 5 of the spiral track to the opening 6, this chute receiving the finished rolls and discharging 20 them into a suitable receptacle (not shown) which is disposed below the opening 6.

As clearly shown in Fig. 4, the track 4 is inclined at such an angle to the horizontal that the upper peripheral surface P of the roll R, which in the case isshown as a tapered roll, always-lies in a horizontal plane which is parallel with the lower surface of the grinding or lapping wheel 3.

The radially outward sidewall 9 of the track 4 is inclined so as to form an angle with the track which is the same as the angle between the thrust end T and the peripheral'surface P of the roll R. The radially inward sidewall. II) of the track may be vertical or inclined in such a way as to leave sufiicient clearance between it and the smaller inner end 'of the roll R to prevent binding of the rolls in the course of their movement along the track.

The roll carrier 2 is mounted on the support I and is provided at its outer edge with a ring 40 gear I I formed integrally therewith and embracing the peripheral surface of the support. The

carrier is provided with a multiplicity of radial slots I2 which are all of the same length and extend from the inner periphery of the ring gear II to a point adjacent the opening 6 in the roll.

support. The carrier is adapted to be driven in thedirection indicated by the arrow in Fig. 1,

as by means of a pinion I3 in mesh with the ring gear I I and which pinion is adapted to be driven bya motor (not shown). The grinding or lapping wheel or disk 3, which is formed of a suitable abrasive material is mounted on a shaft I4, whereby it may be driven in the same direction as the roll carrier. The

- The various parts arethen arranged as shown in Figs. 1 and 2 and the roll carrier and wheel 3 caused to rotate, the speed of rotation of the carrier being less than that of the abrasive wheel.

Due to the fact that the axis of the abrasive wheel 3 is oifset from the axes of the-roll support and carrier, a portion of the left side of the carrier is at all times exposed. This permits the rolls to be ground or lapped to be deposited,

one at a time, in the successive slots I2 at the extreme outer ends thereof. It will be understood, however, that it is not necessary that the axis of the abrasive wheel 3 be offset from the axes of the roll support and carrier, and the abrasive wheel may in fact be coaxial with the latter. In this case, the roll support and carrier will be of larger diameter than the abrasive wheelso as to leave the marginal portion of the carrier exposed suificiently to receive the rolls. 7 In the course of the rotation of the roll carrier, the rolls are caused to traverse the spiral track, and this traversing movement combined with the action of the abrasive wheel, results in a continuous and simultaneous grinding or lapping of the peripheral surfaces of the rolls R and the thrust end surfaces T thereof.

The rolls R roll, but do not slide on the bottom .of the track. Consequently, the track does not exert an abrading action on the peripheral surfaces of the rolls, and the work support, for this reason, may be made of an abrasive material.

The rolling action of the rolls on the track results in a sliding of the surfaces T of the rolls on the sidewall 9. At the samev time, the sidewall of the track forces the rolls towardthe center of the roll support, and thereby exerts a pressure on the surfaces T. Since, as before stated, the sidewall 9 of the track is charged with an abrasive, the result of the aforesaid sliding action and pressure is that abrasion of the thrust end surfaces of the rolls takes place. At the same time the peripheral surface of the roll is continuously ground by the abrasive wheel 3, the abrasive action resulting principally from the difference in speed of rotation of the peripheral surface of the roll and the abrasive wheel, which difference results from and depends upon the difference in speed of rotation of the work carrier and the abrasive wheel. This-abrasive action on the body or peripheral surface of the roll is augmented by virtue of the fact that the roll in the course of its movement from the outer to the inner end of the slot l2 in which it. is disposed crosses the lower surface of the abrasive wheel, and also by virtue of the fact that the abrasive wheel, since it rotates about an axis offset from that of the roll carrier, exerts a shear tion of rolls which are highly accurate as to size. roundness and straightness.

When the rolls reach the inner end of the spiral track, they fall by gravity into the chute l, dropping into a suitable receptacle which is provided therefor below the opening 6 in the roll support.

Owing to the fact that the radius of curvature of the side wall 5 of the track decreases as the track approaches the center of the roll support, this method of grinding or lapping is especially adapted for tapered roller bearings of the Timken type, in which the thrust ends T are slightly inclined with respect to the axis of the roll. In such case the inclination or taper of the thrust end of the roll is developed by a progressive action, that is to say, the lapping action will begin at the point designated a and progress towards the point designated b as the roll approaches the inner end of the track, the points of contact between the sidewall 9 and the thrust end of the roll in eiIect moving radially outwardly from the axis of the roll.

In the ordinary case, however, when it is desired to lap the entire thrust end of the roll during the entire lapping action of the body or peripheral surface of the roll, the roll support will be made so large with relation to the diameter of the rolls to be lapped and the track will terminate at such a distance from the center of the support, that the change in the degree of curvature of the sidewall of the track will be so slight as to avoid the progressive lapping action referred to in the preceding paragraph.

In order to minimize the resistance to rolling of the rolls on the track, the bottom of the track may be crowned as in Fig. 5. By crowning the bottom of the track in this manner, a further advantage is secured in that the body or peripheral surface of the rolls may always be presented parallel to the lower surface of the abrasive wheel, in which case, the abrasive wheel simply finishes this surface of the rolls as it comes to the machine without correcting the taper of the rolls, as is the case where the bottom of the track is tapered to conform with the angle of taper of the rolls.

In that form of the machine shown in Fig. 6, the depth of the track decreases as it approaches the center of the work support. This permits rolls of various diameters to be ground, the rolls passing through a sizing zone, so that all of the rolls are finally ground to the same predeterwall of the track results from the resistance which the rolls encounter to their movement towards the center of the roll support.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the means and the steps herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A machine for grinding or lapping bearing rolls, comprising a stationary substantially horizontally disposed roll support having a spiral track therein 01 across-sectional contour to receive the rolls to be ground or lapped, the radially outer side wall of said track being charged with an abrasive, a rotatable roll carrier mounted V 5 on said support and adapted to cause said rolls to traverse said track, and a rotatable abrasive wheel disposed; above said carrier. j

2. A machine for grinding or'lappingbearing rolls, comprising a stationary roll support having a spiral track therein, a rotatable roll carrier.

mounted on said support and adapted to cause said rolls to traverse said track, and a rotatable Y abrasive wheel disposed above said carrier, the -axis of rotation of said wheel being laterally l5 offset from the axis of rotation of said carrier.

3. The method which comprises lapping the pheripheral surface of a bearing roll while lapping the thrust end surface thereof progressively from a radially inward to a radially outward point on said thrust end surface.

4. A- machine for grinding or lapping bearing rolls; comprising a horizontally disposed roll support having a spiral track in its upper surfaceof a cross-sectional contour to receive the rolls to be ground or lapped, and a rotatable abrasive.

. 3 a spiral track in its upper surface.

port having said track having'a bottom surface for revolubly supporting the body of a roll and a side wall extending at an angle to said bottom-surface and forming an abutment for the. thrust end ofa rolls, comprising a horizontally-disposed roll sup-'- port having a spiral track' in its upper surface, said track having a base forming a sup rtfor the body ofa roll and inclined downwardly from its radially inner edge to its radially outer edge and a side wall extending at an angle to said base and forming anabutment for the thrust end of a roll, and an abrasive wheel disposed above said support.

8. A machine for grinding or lapp bearing rolls, comprising a horizontally disposed roll support having a spiral track in its upper surface of a cross-sectional contour to receive the rolls to be ground or lapped and of varying depth, and a rotatable abrasive wheel disposed above said support. a

'9. A rolls, comprising a horizontally disposed roll support having a spiral track in its upper surface of across-sectional contour to receive the rolls to be ground or lapped and of a depth which gradually decreases from ,the outer to the inner machine for grinding or lapping bearing end of the spiral, and a rotatable abrasive wheel disposed above said support.

- ALVIN B. EINIG. 

